Recent development of networking has created new applications for network communication devices which transmit/receive e-mail messages over the Internet or like network.
Some newly developed network communication devices can not only capture an image with a built-in scanner function, but also forward the captured image information to a computer or like apparatus connected to the network in the form of an attachment to an e-mail message. Internet facsimile machines (hereinafter, “Internet faxes”) have been also developed which incorporate a built-in print function and telephone function in addition to the scanner function.
Referring to FIG. 26, Internet faxes 100, 101 either connect to a host 103, an Internet provider, over a PSTN (Public Switched Telephone Network) 102 or like network and on to the Internet 104 via the host 103 or connect directly to the Internet 104. Internet faxes 100, 101 at the transmitting end and the receiving end transmit/receive e-mail messages while they are being connected to the Internet 104.
A problem occurs under these circumstances where information is transmitted using an e-mail message as in the forgoing: unlike, for example, those cases when information is transmitted by an ordinary facsimile machine, the transmitting end has no means to determine whether the information is received normally or processed properly by the receiving end. Specifically, unlike G3 facsimile machines performing realtime facsimile communication with each other over a PSTN, the transmitting-end machine has no means to determine, upon an e-mail message transmission from the transmitting-end machine, whether the receiving-end machine has normally received or properly processed the e-mail message transmitted from the transmitting-end machine to the receiving-end machine.
Therefore, conventionally, the disposition of an e-mail message must be inconveniently confirmed by a telephone call. The process of transmitting information via e-mail and thereafter confirming the disposition by a telephone call requires redundant action. Also, the process of transmitting information via e-mail and thereafter confirming the disposition by a telephone call causes e-mail communication to lose one of its advantages over telephone communication that the parties involved do not need to talk with each other in real time.
Accordingly, a method is defined by the MDN (Message Disposition Notification) in RFC 2298 which provides a means of notifying of safe disposition of an e-mail message (MDN) whereby upon reception of an e-mail message, the receiving-end machine sends a disposition response back to the transmitting-end machine. This is a method of notifying the transmitting-end machine of reception, progress, etc. regarding the e-mail message at the receiving-end machine by including such information in a message disposition notification in the form of an e-mail message (MDN e-mail message) of a predetermined format. The terms “disposition notification” and “disposition confirmation” are interchangeable. “RFCs” (Requests For Comments) are official documents issued by IETF (Internet Engineering Task Force), an Internet-related technology standards organization. The documents define, for example, specifications and requirements of Internet protocols, such as IP, TCP, HTTP, and FTP, and various Internet-related technologies. They are numbered throughout like “RFC 2298” and publicly available.
The MDN defined in RFC 2298 gives a new “Disposition-Notification-To” field in the header of the e-mail message. Disposition notification is carried out using the field provided that the transmitting-end machine and the receiving-end machine meet the specifications. Specifically, the transmitting-end machine specifies an address in the field to which a disposition notification message should be directed before transmitting the e-mail message, and the receiving-end machine sends an MDN e-mail message to the address specified in the field.
Now, procedures in confirming disposition according to the aforementioned MDN will be described in reference to FIG. 27(a) and FIG. 27(b). Referring to FIG. 27(a), to carry out a disposition notification according to the MDN defined by RFC 2298, first, the following procedures are sequentially implemented as a transmission operation (composition of an e-mail message) at the transmitting end:    1) The user places an original document to be transmitted on a scanner of the transmitting-end machine.    2) The user inputs the e-mail address of the transmission destination to the transmitting-end machine.    3) The user inputs a file format (PDF, TIFF, etc.) for the original document to be transmitted to the transmitting-end machine.    4) The transmitting-end machine captures the original document to prepare an e-mail message for transmission.
If an MDN is to be requested, a “Disposition-Notification-To” field is included in the header of the e-mail message being composed in the e-mail message composition in 4) above.
Meanwhile, the following procedures are sequentially implemented as a reception operation at the receiving end having received an e-mail message.    5) The receiving-end machine recognizes the header of the received e-mail message and implements a confirmation process to check, for example, whether there is any abnormality in the attachment data.    6) The receiving-end machine prints out the received e-mail message.    7) The receiving-end machine composes an MDN e-mail message if it has recognized a “Disposition-Notification-To” field.    8) The receiving-end machine sends the MDN e-mail message to the recipient address specified in the “Disposition-Notification-To” field.
A disposition notification is thus implemented using a “Disposition-Notification-To” field.
Trouble may arise as in as shown in FIG. 27(b) where, as an example, the receiving-end machine receiving an e-mail message transmitted from the transmitting-end machine is unable to print the e-mail message. When this is the case, the receiving-end machine composes an MDN e-mail message notifying of the occurrence of abnormality and sends to the recipient address specified in the “Disposition-Notification-To” field.
Japanese Published Unexamined Patent Application 2001-309109 (Tokukai 2001-309109, published on Nov. 2, 2001) discloses a facsimile machine implementing an MDN method. If an MDN request is sent without receiving an MDN e-mail message from the receiving-end machine within a certain period of time, the facsimile machine outputs a disposition failure alert to notify the user that it has received no MDN e-mail message.
The aforementioned conventional technology has following problems. The user often uses an Internet fax in a similar manner to an ordinary facsimile machine. The user is highly likely to make a setting to request a disposition notification by MDN.
When this is the case, according to the aforementioned conventional technology, an MDN e-mail message is returned at a different time for each e-mail message even when, for example, two or more e-mail messages were successively transmitted, and only a single, collective disposition notification is required after completely transmitting all the e-mail messages.
More specifically, suppose that three e-mail messages were successively transmitted to the same recipient address with 10 minute intervals. A total of three MDN e-mail messages corresponding to the transmitted e-mail messages are then returned with 10 minute intervals. Therefore, every time an MDN e-mail message is returned, the fax machine displays the content of the MDN e-mail message on screen or outputs a transmission report describing the content of the MDN e-mail message, as shown in FIG. 28. Such disposition notification is burdensome to the user.
Here, the main text of the return message includes a message ID which is an identifier actually used in MDN to show which received e-mail message corresponds to which transmitted e-mail message. However, the displayed content is not so limited: for example, the user may be notified of the subject of the transmitted e-mail message, transmission time, and other information.
Another shortcoming in the context of network communication is an undesirable, increased network traffic generated by the transmission, to the transmitting end, of the return messages individually composed for the transmitted e-mail messages.